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          <th colspan="3" align="center">DB_ENV-&gt;set_memory_max()</th>
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            <h2 class="title" style="clear: both"><a id="envset_memory_max"></a>DB_ENV-&gt;set_memory_max()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;set_memory_max(DB_ENV *dbenv, u_int32_t gbytes, u_int32_t bytes); </pre>
      <p>
        This method sets the maximum amount of memory to be used by shared
        structures in the main environment region.  These are the
        structures used to coordinate access to the environment other than
        mutexes and those in the page cache (memory pool).  If the region
        files are in memory mapped files,  or if
        <code class="literal">DB_PRIVATE</code> is specified, the memory specified by
        this method is not allocated completely at startup.  As memory is
        needed, the shared region will be extended or, in the case of
        <code class="literal">DB_PRIVATE</code>, more memory will be allocated using
        the system malloc call.  For memory mapped files, a mapped region
        will be allocated to this size but the underlying file will only be
        allocated sufficient memory to hold the initial allocation of
        shared memory structures as set by
	<a class="xref" href="envset_memory_init.html" title="DB_ENV-&gt;set_memory_init()">DB_ENV-&gt;set_memory_init()</a>.
    </p>
      <p>
        If no memory maximum is specified then it is calculated from
        defaults, initial settings or (deprecated) maximum settings of the
        various shared structures.  In the case of environments created
        with <code class="literal">DB_PRIVATE</code>, no maximum need be set and the
        shared structure allocation will grow as needed until the process
        memory limit is exhausted.
    </p>
      <p>
         The database environment's maximum memory  may also be configured
         using the environment's 
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 
         file.  The syntax of the entry in that file is a single line with
         the string "set_memory_max", one or more whitespace characters,
         followed by the maximum to be allocated. Because the 
         <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 
         file is read when the database environment is opened, it will
         silently overrule configuration done before that time.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;set_memory_max()</code> method must be
         called prior to opening the database environment.
    </p>
      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idm140711177387488"></a>Parameters</h3>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idm140711177307328"></a>gbytes</h4>
              </div>
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          <p>
                    The maximum memory is set to 
                    <span class="bold"><strong>gbytes</strong></span> gigabytes plus
                    <span class="bold"><strong>bytes</strong></span>.
                </p>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
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              <div>
                <h4 class="title"><a id="idm140711177305632"></a>bytes</h4>
              </div>
            </div>
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          <p>
                    The maximum memory is set to 
                    <span class="bold"><strong>gbytes</strong></span> gigabytes plus
                    <span class="bold"><strong>bytes</strong></span>.
                </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idm140711177297648"></a>Errors</h3>
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        <p>
                The <code class="methodname">DB_ENV-&gt;set_memory_max()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idm140711177288432"></a>EINVAL</h4>
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          <p>
                If the method was called after <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a> 
                was called; or if an invalid flag value or parameter was specified.
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              <h3 class="title"><a id="idm140711177285840"></a>Class</h3>
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        <p>
            <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
        </p>
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              <h3 class="title"><a id="idm140711177314560"></a>See Also</h3>
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        <p>
             <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 
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